The present invention relates to a semiconductor device and a manufacturing method of the same, and can be suitably used for a power semiconductor device and a manufacturing method thereof, for example.
In a vertical power MOSFET that is a power semiconductor device, employment of a superjunction structure has been studied in order to reduce an on-state resistance while keeping a breakdown voltage.
For example, the disclosure of Wataru Saito et al., “Influence of Carrier Lifetime Control Process in Superjunction MOSFET Characteristics”, Proceedings of the 26th International Symposium on Semiconductor Device & IC's, Jun. 15-19, 2014 Waikolao, Hi. aims to improve a recovery speed of a built-in diode of a MOSFET having a superjunction structure, and in FIG. 1 a technique is disclosed that radiates an electron beam into a substrate or a technique that dopes the substrate with Pt in order to control a lifetime of carriers.